OK i've looked high and low and I want to get female .1" straight header pins with the long leads on the bottom like on the ethernet Arduino shield. I'm trying to build a shield of my own. Where do i get them in the US? I've contacted digikey and newark and neither one seam to know what I'm talking about.

It's a "Tail option" on Samtec's SSW line of connectors (for example; I imaging other manufacturers do similar things.)

http://www.samtec.com/ftppub/pdf/SSW_TH.PDF

Samtec is a great manufacturer; been in business forever, generous with samples, generally helpful and communicative, and available through digikey. (I don't know if you can get ALL samtec parts through digikey, though...)

They're 6 and 8 - way long-tailed 0.1" pitch sockets.The 'F' is for "gold flash selective" (gold flash inside the sockets) but with Matte tin on the tails.I went for the 'low insertion force' (the '23' in the part) and it seems just right.I'm assuming that matte tin is OK to use as a connecting pin.

I too put in an order, but I ended up with headers that don't quite fit. I got the SSW models, which have slightly wider pins, and went with standard insertion force - it is tough to get those suckers in. Like you said though, the samtec fulfillment is super fast!

Also, anyone who ends up ordering some of these, be aware that they do not fit flush against the headers on the Arduino. The pins on this size are just a tad bit long. Presumably you could clip them... but just a heads up.

@sircastor: Order them with 2 spacers on the top. That way you have more space on the top of your PCB and it plugs fully into the one below. Note, make sure that you don't put thru hole components over the ethernet or it will touch them.